Herpes Simplex Virus 1 (HSV-1) is an enveloped DNA virus, with high incidence, long latency, perineural, and incubating in peripheral nervous system. Young children, organ transplant recipients or people with diminished immunity are susceptible to infection of HSV-1 virus. Once infected, HSV-1 virus can cause serious encephalitis, keratitis and even death. Nucleoside antiviral medications, such as acyclovir, famciclovir, and valacyclovir, are the most effective medications available for people infected with HSV. These medications can help to reduce the severity and frequency of symptoms, but cannot cure the infection. In view of the increasing cases of drug-resistant pathogens, it is imperative to develop new and effective antiviral drugs. Marine microorganisms are widely recognized as prolific sources of biologically active and structurally unique natural products because of their unique living condition such as high salinity, high pressure, low temperature, oxygen deficiency and darkness. However, there are few reports of marine-derived antiviral entity. (Newman, D. J.; Cragg, G. M. J. Nat. Prod. (2012) 75:311-335; Blunt, J. W.; Copp, B. R.; Keyzers, R. A.; Munro, M. H. G.; Prinsep, M. R. Nat. Prod. Rep. (2014) 31:160-258, and previous annual reports). Thus, there is a need of developing new and effective antiviral drugs.